It is easy to walk past without registering what it is. The site never appeared on the historic Ordnance Survey maps of Ireland, and it was only through aerial photography in the 2000s that the curving footings of its enclosure wall became clearly legible from above. What those images reveal is the outline of a settlement platform roughly 34 metres long and 20 metres wide, bounded on its east and west sides by natural limestone outcrops and enclosed on at least three sides by a double-kerbed wall of upright stones, with only the southern edge facing the lake left open.

Excavation here, carried out in 1954 as part of a long campaign of eighteen seasons of fieldwork led by Professor Seán P. Ó Ríordáin, established that this was a late Neolithic habitation site associated with the Beaker period, a phase of prehistoric culture named for its distinctive pottery. A Beaker-period enclosure like this one typically represents a community making deliberate use of the landscape, choosing a naturally defensible or bounded platform and then reinforcing that boundary with architecture. The site appears to have begun as an open settlement with a poorly defined house, and only in a second phase was the double-kerbed wall constructed to cut off the habitation area from the rest of the peninsula. Finds included flint tools, arrowheads, stone axes, perforated bone and stone discs, beads, and a substantial collection of pottery. The presence of a small quantity of Food Vessel pottery, a type associated with the Early Bronze Age, suggests the site continued to be occupied after the Neolithic period ended. The results were published posthumously by Eoin Grogan and Professor George Eogan in 1987, some time after Ó Ríordáin's death.

The Knockadoon Peninsula is exceptionally dense with prehistoric remains, and this site sits within a cluster of excavated locations, with other sites investigated by Ó Ríordáin within fifty to eighty metres in several directions. The stone circle known as Circle K lies roughly 175 metres to the north-east. The enclosure bank and its orthostatic wall, meaning a wall built from upright slabs rather than coursed masonry, are still visible on the ground and on recent satellite imagery. The ground to the south-west falls away in broad geological steps toward the lake shore, giving the platform a naturally sheltered quality that is still apparent when you stand on it. A three-dimensional model of the monument is available online via Sketchfab at the reference skfb.ly/osqZR, which is worth consulting before or after a visit to understand the full extent of the surviving remains.